The fourth-ranked search engine, Ask.com, got only 2.56 percent of U.S. searches during the month, while another 52 search engines in the Hitwise Search Engine Analysis Tool accounted for just 1 percent of U.S. searches combined, Hitwise reported.

This news for small business owners and entrepreneurs means search engine optimization (SEO) and website marketing through blogs and social media may need to target customers using more than one portal.

Although Facebook accounted for 58.59 percent of all U.S. visits to 155 social networking websites in September 2009, MySpace still attracts 30 percent of all social network users, Hitwise reported.

Tagged received 2.38 percent of visits in September 2009, followed by Twitter with about 2 percent of all visits in the month.

A recent survey by Citibank indicates that many small business owners are not taking advantage of the marketing potential of Facebook, MySpace and Twitter, but those that do are generating sales leads through the services, according to Officialwire.com.